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3 years ago

Here is to the people who need points (again) Have a good day!

Engineering

2 answers:

alexdok [17]3 years ago

8 0

Thank you so much!! You too!

g100num [7]3 years ago

7 0

Answer:

SERIOUSLY! TY

Explanation:

I don't think you understand how much this is gonna help me out :) Have an amazing summer! Stay safe!

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Describe what V1-V4 is

photoshop1234 [79]

Answer:

it is wave inversion

Explanation:

8 0

3 years ago

The yellow rectangle area is 25% (or 1/4) the area of the blue rhombus. The height (H) of the yellow rectangle is twice as long

Kitty [74]

Answer:

I don't know sry

Explanation:

6 0

3 years ago

Water at atmospheric pressure boils on the surface of a large horizontal copper tube. The heat flux is 90% of the critical value

masya89 [10]

Answer:

The tube surface temperature immediately after installation is 120.4°C and after prolonged service is 110.8°C

Explanation:

The properties of water at 100°C and 1 atm are:

pL = 957.9 kg/m³

pV = 0.596 kg/m³

ΔHL = 2257 kJ/kg

CpL = 4.217 kJ/kg K

uL = 279x10⁻⁶Ns/m²

KL = 0.68 W/m K

σ = 58.9x10³N/m

When the water boils on the surface its heat flux is:

$q=0.149h_{fg} \rho _{v} (\frac{\sigma (\rho _{L}-\rho _{v})}{\rho _{v}^{2} } )^{1/4} =0.149*2257*0.596*(\frac{58.9x10^{-3}*(957.9-0.596) }{0.596^{2} } )^{1/4} =18703.42W/m^{2}$

For copper-water, the properties are:

Cfg = 0.0128

The heat flux is:

qn = 0.9 * 18703.42 = 16833.078 W/m²

$q_{n} =uK(\frac{g(\rho_{L}-\rho _{v}) }{\sigma })^{1/2} (\frac{c_{pL}*deltaT }{c_{fg}h_{fg}Pr } \\16833.078=279x10^{-6} *2257x10^{3} (\frac{9.8*(957.9-0.596)}{0.596} )^{1/2} *(\frac{4.127x10^{3}*delta-T }{0.0128*2257x10^{3}*1.76 } )^{3} \\delta-T=20.4$

The tube surface temperature immediately after installation is:

Tinst = 100 + 20.4 = 120.4°C

For rough surfaces, Cfg = 0.0068. Using the same equation:

ΔT = 10.8°C

The tube surface temperature after prolonged service is:

Tprolo = 100 + 10.8 = 110.8°C

8 0

3 years ago

Sinks must be used for the correct intended purpose to prevent

irakobra [83]

Answer:

... spilling water or getting anything cascading onto the floor

8 0

3 years ago

Technician A says that a way to prevent galvanic corrosion is to duplicate the original installation method. Technician B says t

sertanlavr [38]

Answer:

Technician A

Explanation:

Galvanic corrosion is not on only one metal alone but caused when two metals are interacting. Thus, Duplicating the original installation method is a better option because re-using a coated bolt doesn't prevent galvanic corrosion because both materials must be coated and not just the bolt and in technician B's case he is coating just the bolt. Thus, technician B's method will not achieve prevention of galvanic corrosion but technician A's method will achieve it.

8 0

2 years ago

Here is to the people who need points (*again*) Have a good day!

Here is to the people who need points (again) Have a good day!